2009-2011年深圳市头孢曲松低敏淋病奈瑟菌的流行特征

Molecular characteristics of Neisseria gonorrhoeae isolates with decreased susceptibilities to ceftriaxone in Shenzhen from 2009 to 2011

目的 调查2009-2011年深圳市头孢曲松低敏淋病奈瑟菌（淋球菌）流行的基因型和特征.方法 收集2009至201 1年深圳市淋球菌296株,采用琼脂稀释法筛选出头孢曲松低敏株（最小抑菌浓度为0.06 ～0.50 μg/ml）,用logistic回归分析方法,分析与头孢曲松低敏淋球菌感染相关的因素；根据1∶1抽样原则抽取出高敏菌株,与低敏菌株一起进行淋病奈瑟菌抗原序列分析（NG-MAST）基因分型和邻接法（neighbor-joining,NJ）进化树分析.结果 在296株淋球菌中,未发现头孢曲松耐药菌株,头孢曲松低敏菌株53株（17.9％）.近2个月的抗生素使用史与头孢曲松低敏淋球菌感染相关（OR=3.080,95％ CI：1.376 ～6.894）.53株低敏株的NG-MAST共得到48个ST型,由5个成簇的ST（ST1768、ST3927、ST641、ST7076、ST7078各包含了2株淋球菌）和43个单一的ST构成,其中26个ST型中国香港等地曾有报道.NJ进化树未观察到低敏株单独成簇的情况.结论 深圳市2009-2011年分离到的296株淋球菌中头孢曲松低敏株的比例较高；深圳市头孢曲松低敏淋球菌菌株的流行可能有其独特的特点.

Objective To investigate the genotype and characteristics of Neisseria gonorrhoeae （N.gonorrhoeae） isolates with reduced susceptibility to ceftriaxone in Shenzhen from 2009 to 2011.Methods A total of 296 N.gonorrhoeae isolates were collected in Shenzhen from 2009 to 2011.ceftriaxone strains （minimum inhibitory concentration between 0.06 and 0.50 μg/ml） were determined by agar dilution method.Logistic regression was used to analyze the associated factors of ceftriaxone N.gonorrhoeae infection.Neighbor-joining（NJ） phylogenetic tree analysis and N.gonorrhoeae multiantigen sequence typing （NG-MAST） were performed on all ceftriaxone isolates and susceptible control isolates randomly selected in accordance with the principle of 1 ∶ 1 sampling.Results No isolates displayed resistance to ceftriaxone,whereas 53 （17.9％） showed reduced susceptibility to ceftriaxone among 296 isolates.Only antibiotic use in recent two months was associated with ceftriaxone isolates infection（OR =3.080,95％ CI：1.376-6.894）.Among the ceftriaxone isolates,48 different ST were identified including 5 STs （ST1768,ST3927,ST641,ST7076 and ST7078） containing 2 isolates and 43 single STs.There were 26 STs previously reported from HongKong in China.Low sensitive strains clustering was not observed by NJ phylogenetic tree.Conclusion The proportion of ceftriaxone strains among the 296 N.gonorrhoeae isolates collected from 2009 to 2011 in Shenzhen is high.The STs of ceftriaxone strains may have unique epidemic features in Shenzhen.